Unfair Billing

I have had nothing but PROBLEMS with Xfinity since 2017 to the degree that it forced me to cancel my cable but keep the internet service because I work from home. Xfinity likes to rack up years worth of late charges then out of the blue they tell you there’s a past due balance on top of another past due balance plus late additional late fees. Even if your bill is current across the board you still need to check your statement. They say you won’t be charged for a in-house service call but later find they charged you $100. It took forever for me to get that removed. I admit I am behind in my bill but my payment always includes the late charge so why is there a past due balance of $49.07 plus $109.24. Doesn’t match the statement. XFINITY cannot be trusted and I am filing a consumer complaint.